In wireless communication systems, a radio access network generally comprises one or more access nodes (such as a base station) which communicate on radio channels over a radio or air interface with plural wireless terminals. In some technologies such a wireless terminal is also called a User Equipment (UE). A group known as the 3rd Generation Partnership Project (“3GPP”) has undertaken to define globally applicable technical specifications and technical reports for present and future generation wireless communication systems. The 3GPP Long Term Evolution (“LTE”) and 3GPP LTE Advanced (LTE-A) are projects to improve an earlier Universal Mobile Telecommunications System (“UMTS”) mobile phone or device standard in a manner to cope with future requirements.
In typical cellular mobile communication systems, the base station broadcasts on the radio channels certain information which is required for mobile stations to access to the network. In Long-Term Evolution (LTE) and LTE Advanced (LTE-A), such information is called “system information” (“SI”). Each access node, such as an evolved NodeB (“eNB”), broadcasts such system information to its coverage area via several System Information Blocks (SIBs) on downlink radio resources allocated to the access node.
A wireless terminal (“UE”), after entering a coverage area of an eNB, is required to obtain all the SIBs which are necessary to access to the system. For sake of UEs under coverage, the eNB periodically broadcasts all SIBs relevant for offered services, not just SIBs that are required for access to the system. Each type of SIBs is transmitted in a designated radio resource(s) with its own pre-determined/configurable frequency.
This all-broadcast-based periodic delivery method (e.g., collective broadcast of all SIBs, not just those necessary for system access) is efficient under a condition where many UEs are almost always flowing into the coverage area (such as a macro cell). However, this approach may result in wasting valuable radio resources in case of small cell deployment. Therefore, more efficient methods of SIB transmission are desired.
What is needed, therefore, and an example object of the technology disclosed herein, are methods, apparatus, and techniques for more efficient transmission of system information blocks (SIBs).